Jet motor with cooling system



May 23, 1950 M. J. ZUCROW v JET MOTOR WITH COOLING SYSTEM Original Filed July 14, 1944 I N V EN TLR.

AMUR/CE J. ZUCROW (7 Arron/i22 Patented May 23, 1950 UNITED STATES PATENT OFFICE JET MOTOR WITH COOLING SYSTEM Maurice J. Zucrow, Altadcna, Calif assignor to arszsmaszsaex Mm Original application July 14, 1944, Serial No.

544,868- Divided and this application 1945, Serial No. 805.305

12 Claims. (CI. 60-35.)

This invention relates to jet propulsion motors and methods for operating the same and has for its object the improvement of the operating performance of such motors.

This application is a division of my copend- 11:4 application Serial No. 544,868, flled July 14, i

Jet propulsion motors have heretofore been operated by burning fuel in av combustion chamber and causing the ensuing products of combustion to be ejected through an exhaust nozale to create the propulsion force.

Good performance has been obtained by injecting two propellant liquids into the combustion chamber, one a fuel and the other an oxidizer for the fuel; for example, aniline has been used as a fuel and red fuming nitric acid as an oxidizer. These two liquids have been injected separately into the combustion chamber and caused to impinge upon each other, whereupon spontaneous combustion takes place, liberating a large amount of gases which escape through the exhaust nozzle in the form of a jet.

The combustion in the combustion chamber develops great heat, and the hot gases passing through the nozzle heat up the nozzle considerably. It is desired to provide coolant for the nozzle and the chamber and also to take care of expansions of the parts at the elevated ternperatures.

In accordance with the present invention, there is provided means for passing a cooling fluid along the outside wall of the nozzle. Preferably the path of the coolant is in spiral convolutions around the nozzle wall.

A related feature is the provision of a space or passageway for cooling fluid flow around the combustion chamber.

A related feature is the provision of a passageway communicating from the coolant space around the chamber to the spiral convolutions around the nozzle.

' A further feature of the invention is the provision of an annular element around the nozzle and forming a boundary for the spiral convolution. provision being made -i'or expansion or the 'parts due to heat. According to a preferred iunction with the drawin in which:

Ill! 18,

2 Fig. l is an elevational view in cross section of a jet propulsion motor embodying my invention; and

Fig. 2 is a cross sectional view at line 2-2 oi Fig. 1.

Similar numerals refer to similar parts in the I views.

The motor shown in Fig. 1 comprises a combustion chamber formed by the wall I in the shape of a portion of a sphere, and an exhaust nozzle 2 protruding from the chamber. The combustion chamber may be made of a suitable metal such as steel and may conveniently be of two parts, as shown, there being a hemispherical the shoulder flange ll being recessed as shown at l2. The wall of the exhaust nozzle 2 contracts towarda constricted portion I! from the recess i2. and from the constricted portion it the nozzle flares outwardly to an enlarged opening it. Another flange I! welded at it to the enlarged portion It continues substantially the general outline of the exhaust nozzle forming a recess at I1 and a thickened section i8 which provides the necessary material for the threads of the screws IS. The flange i5 is machined to receive bolt ring 20 and machined to complete the general outline of the exhaust nozzle at 2|.

In Figs. 1 and 2 the exhaust nozzle is shown as being surrounded by a jacket 23 arranged to provide a fluid flow spirally from an inlet 24 for cooling liquid at the extreme end of the exhaust nozzle toward a chamber A around the combustion chamber. A spiral member 22 formed integrally with the wall 2 of the exhaust nozzle, or welded to it. forms this spiral passage. At the front end 2i of the exhaust nozzle the area of the fluid passage is larger than at the throat I 3 of the exhaust nozzle. The construction accomnlishes this by the factthat at the throat is the hei ht of the convolutions of the spiral. for exam le. convolution 25"is less away from the throat than convolution 28 on one side .and 21 on the other. I and 29 are nlaced aroundthe s iral at the' nozzle, the two halves being bolted together by bolts 2|.

(Fig. 2) which are secured in place'by nuts".

(Fig. 2). The inner curved surfaces of mem- A pair of solid members 22 hers 28 and 28 fit snugly against the the spiral so that the maid passageway at the throat is (Fig. 1) near as hm less area nut near the more remote convolutions 2t and all. The outer cylindrical suriaces or members 28 and 29 match the inner surrace' of the iacket 23.

' to the tubular member es. Disc at has a con- Qne or a plurality or grooves 32 are machined around members 26 and Z9 and into each groove an O ring 33 is snapped providing a mild-tight asoseo with nut 58.

contact between members 28 and 29 and the tubular jacket 23. The coolant inlet as communicates with the spiral convolution which is nearest to the end of the exhaust nozzle 2. The j tubular jacket 23 is welded to the bolt ring 29. By inserting screws i9 through the bolt ring and screwing them into the e ii the exhaust nozzle is thereby removably iastened to the tubular member 23.

The tubular jacket is provided with aprotruding ring 34 which acts as a retainer on one side for another 0 ring 35. The O ring 35 flts between the tubular jacket 23 and a tubular member 36 which surrounds jacket 23. Tubular member 36 contains another ring 31 protruding towards the center of member 36. Ring 31 acts as another retainer for the O ring 35. A tubular member 38 suitably welded or attached to member 33, flares outwardly to form a spherical jacket-39 conforming with and surrounding the member 5 of the combustion chamber. The space between the chamber and outer jacket 39 is'the chamber A, adapted to receive and contain the liquid received from the spiral convolutions 22. Another hemispherical member 42 is welded at M to the elongated member 39. Continuation oi chamber A is provided between the members 3 and t2.

In the extreme portion oi the hemispherical member 42 there is provided an outlet 63 for the coolant liquid. .9. refractory liner M is placed against the inner wall of the hemispherical portion 3 of the combustion chamber and held in place by the inserted refractory liner 45 which is held in place by collar ill of the exhaust nozzle.

The refractory liners may be of any suitable refractory material, for example, tungsten, tungsten carbide, silicon carbide, boron carbide, calcium oxalate, carbon (graphite), magnesium oxide, molybdenum carbide, zirconium carbide, zirconium oxide or any other standard retractories such as mullite, transite, mixture of carlion and asbestos, or other like substances.

A plurality of propellant injectors are provided, two or which are shown in detail. For a simplifled description I select the upper injector 460 shown in the drawing. At a portion of the member 39 a tubular member 41 having a. rectanglilar flange 43 is welded thereto. The tubular member 41 projects through chamber A into the hemispherical member 6 to which it is also welded.

Another tubular member 48 having in one end a wall Ii and a rectangular flange it is inserted into the tubular member 41. Flange ill of the tubular member 43 is seated on a gasket It can be recognized in accordance with my invention that I have provided a hquid operated 'jet motor in whichthe heat generated by the reaction within the combustion chamber is absorbed in part through -a cooling jacket in conjunction with a plurality of liners. This greatly extends the life of the motor. I have iurther provided for expansion of all metal parts in my novel motor, which necessarily would occur when these parts become heated, and which it not compensated in some manner would soon distort and rupture the motor.

I claim:

1. In a jet thrust motor, the combination comprising a combustion chamber having a flange, said flange having'internal threads for receiving the threaded collar of a replaceable exhaust nozzle, said exhaust nozzle having external spiral convolutions, a convex member surrounding said convolutions and having a cylindrical outer surface, a casing enclosing said outer surface, said casing having a flexible ring for establishing a liquid-tight Joint between said casing and cylindrical outer surface of said convex member, said casing having a protruding ring member for locating a second flexible ring, a tubular member surrounding said protruding ring mem- & ber, said tubular member being in contact with another casing enveloping said combustion chamber, said casing and said combustion cham= ber being arranged in spaced relation as to provide a space for a coolant fluid, so that said coolant may flow through said convolutions and said space,- thereby cooling said combustion chamber and said exhaust nozzle.

2. In a jet thrust motor the combination according to claim 1 in which a ceramic liner covers the inner wall of said combustion chamber to protect the wall from the heat of combustion.

3. In combination with a Jet motor, a combustion chamber having an inner wall and an outer wall forming between them a space for the passage of cooling fluid, an exhaust nozzle attached to the outlet from the chamber, said nozzle having an inner wall and an outer wall forming between them a second space for the passage of cooling fluid, means for attaching the nozzle to the chamber so that the cooling fluid spaces communicate with each other, said means comprising fastening means for fastening one wall of the chamber to the corresponding wall of the nozzle, and means for placing, the other wall of the chamber in sliding relation to the other well of the nozzle, sealing means between the sliding walls whereby the sliding of the walls takes care of expansion due to temperature changes without permitting leakage of the fluid.

4. In combination with a Jet motor having a combustion chamber provided with an inner wall and an outer wall forming between them a space for the pe of cooling fluid, means for ata,soa,soo

taching to the outlet from the chamber an exhaust nozzle having an inner wall and an outer wall forming between them a second space for the passage of cooling fluid, said means comprising a threaded member on the inner wall of the chamber and a threaded member on the inner wall of the nozzle adapted to engage the threaded member of the chamber, the outer walls of the chamber and nozzle being arranged to form a sliding fit one within the other, and a liquid seal between the last two mentioned walls, whereby the cooling fluid spaces of the nozzle and the combustion chamber communicates with each other.

5. Apparatus according to claim 4 in which the outer wall of the nozzle is attached to the inner wall of the nozzle at a position remote from the combustion chamber.

6. Apparatus according to claim 4 in which the cooling space of the nozzle is spiral, one end of the spiral having an inlet for the cooling fluid and the other end of the spiral communicating with the cooling fluid space around the chamber.

7. In a jet thrust motor, the combination comprising a combustion chamber and an exhaust nozzle, the outer wall of said nozzle having spiral convolutions, a convex member surrounding said convolutions and having a cylindrical outer surface, a casing enveloping said outer surface, a second casing enveloping said combustion chamber, means for engaging said flrst mentioned casing with said second casing, a space between the second casing and the outer wall of the combustion chamber for fluid flow and a passageway from said space to the inside of the first casing and communicating with said convolutions whereby the coolant fluid can flow through said convolutions and around said combustion chamber.

8. In a jet thrust motor the combination comprising a combustion chamber, an exhaust nozzle, the outer wall of said exhaust nozzle having spiral convolutions, a convex member surrounding said convolutions and having a cylindrical outer surface, a casing enveloping said outer surface, said casing having means for establishing a liquid tight joint between said casing and said cylindrical outer surface of said convex member, said casing having a protruding ring member, a flexible ring located by said protruding ring member, a tubular member surrounding said protruding ring member and the said flexible ring, said tubular member having an internal ring member for securing said flexible ring, a second casing enveloping said combustion chambar and in contact with said tubular member, said last mentioned casing and said combustion chamber being arranged in such a manner as to provide a space for a coolant fluid between the last-mentioned casing and the combustion chamber, said space being in communication with said convolutions so that said coolant may flow through said convolutions and said space.

9. In a jet thrust motor the combination comprising a combustion chamber, an exhaust nmzle, the outer wall of said exhaust nozzle having spiral convolutions, a convex member surrounding said convolutions and having a cylindrical outer surface, a casing enveloping said outer surface, said casing having means for establishing a liquid tight joint between said casing and said cylindrical outer surface of said convex member, said casing having a protruding ring memcording to claim 'I, in which a ceramic liner covers the inner wall of said combustion chamber to protect the wall from the heat of combustion.

MAURICE J. ZUCROW.

REFERENCES CITED The following references are of record in the tlle of this patent:

UNITED STATES PATENTS Number Name Date 769,379 Herold Sept. 6, 1904 897,503 Wedekind Sept. 1, 1908 919,895 Lemale Apr. 27, 1909 1,856,552 Hadamlk et al. May 3, 1932 1,954,454 McFarland Apr. 10, 1934 2,078,950 Lysholm May 4, 193'! 2,145,507 Denoix Jan. 31, 1939 2,272,194 Frances Feb. 10, 1942 FOREIGN PATENTS Number Country Date 148,823 Great Britain Feb. 9, 1922 OTHER REFERENCES Ser. No. 215,792, Neugebauer et al. (A. P. 0.), published April 27, 1943. 

